Signments



(No Model.) I

- G. T. WOODS.

INDUCTION TELEGRAPH SYSTEM.

Patented Nov. 29, 1887.

1L i L r I i r W1 7 NESSES: IIVVENTOR 3 BMW ATTORNEY N. rcvips. l'mwmrw. 314mm 0, C4

- UNITED STATES PATENT OFFICE.

GRANVILLE T. WOODS, OF CINCINNATI, OHIO, ASSIGNOR, BY MESNE AS- SIGNMENTS, TO THE WOODS ELECTRIC COMPANY.

INDUCTION-TELEGRAPH SYSTEM.

SPECIFICATION forming part of Letters Patent No. 373,915. dated November 29, 1887.

(No model.)

To all whom, it may concern.-

Be it known that I, GRANVILLE T. WooDs, a citizen of the United States, residing at Cincinnati, Ohio, have invented new and useful Improvements in Induction-Telegraph Systems, of which the following is aspeciiication.

My invention relates to systems of electric communication between two moving railway trains or vehicles, or between the same and a fixed station or stations, and transmits the signals to and from the vehicle by means of induction, whereby an electric impulse upon the line-conductor (which, for the purposes of my invention, is formed as a helix surrounding a magnetic core, as in the ease of the ordinary electro-magnet) is caused to produce a corresponding impulse upon the similarlyarranged helix carried by the vehicle in close proximity to the line-conductor, the arrangement being such that the current flowing through the line-helix will pass along one side of the suspended and movable helix, and, returning, will pass along the other side of the suspended helixi The line-conductor may be placed in any convenient position, either upon the ground or upon suitable supports elevated over the roadway, the movable helix being carried by the vehicle in convenient proximity thereto. By this system suitable inductive proximity of the line-magnet and the suspended magnet is all that is required, direct electrical connection between the helices of said respective magnets being unnecessary.

lt is well known to electricians that when two electro-magnets are in suitable inductive proximity and relation to each other, if one of the magnets is suddenly excited the other magnet is excited inductively by the first, and the excitement of the second magnet induces electrical currents in the helix surrounding it. I may therefore inclose the line helix and magnet in a suitable insulating-covering, and as the helix may be thus thoroughly insulated, there will be practically no leakage of the current to the ground.

Any code of signals may be employed in my system of communication. A telephone receiver and a telegraph relay maybe arranged so that either one may cut into the helical circuit when a signal is to be received.

My invention may be said, therefore, to consist, broadly, in a system of communication between moving vehicles, or between such vehicles and fixed stations, in which a continuous metallic return-circuitis employed, arranged as a helix upon a metallic core, for the line-conductor, and a similarly-arranged helix is employed upon the vehicle, moving in inductive proximity to the line-conductor. I also employ normally-open circuits withintermittent currents, as more fully hereinafter set forth.

My invention is illustrated inthe accompanying drawings, in which- Figure 1 is a diagram elevation ofaportion ofa railway-car, showing the apparatus connected therewith for receiving and transmitting signals. Fig. 2 is a plan diagram of one end of the permanent conductor as arranged for operation inductively, it being premised that the central helix is to be connected with apparatus at the receiving-station similar to that shown inFig. 1. Fig. 3 is a plan diagram of the permanent conductors, in which the hclicesof the outgoing and incoming conductors are connected directly with the receiving and transmitting apparatus. Fig. 4 is an end elevation of a railway-car and cross-section of a track, showing the relative arrangement of the conductors. Fig. 5 is a diagram of a portable apparatus to be used in case of accidents to communicate with other moving vehicles or with the permanent stations.

Referring now to the drawings, A and A rep resent wires connecting the receiving or transmitting apparatus with the induction -helix 0 of the car or with the permanent conductors B and B, which latter, for convenience, are preferably placed upon the cross ties of the railway within and parallel to the tracks.

The receiving and transmitting apparatus is the same whether used upon the car or at the permanent stations. The apparatus shown in Fig. 1 therefore may be considered a seniployed either upon the car and connected with the helix 0 or at the permanent station and connected with the permanent conductors B and B.

Commencing, then, with the apparatus used upon the car, C represents an endless core, 100

and the latter with the armature C of the relay-instrument D, parts of the apparatus hereinafter more fully described.

The portion of the apparatus marked 0 may be made by coiling soft-iron wire until the desired thickness for the core is obtained, the core itself being surrounded by a helix of insulated wire, the terminal of which is indicated in Fig. 1, connected by the conductors A and A, respectively, with the circuit-closing key 0' and the relay-armature C. The apparatus, of which these form a part, is'a normally-open circuit by the interposition of a condenser, L, between the key 0 and the telephonic and relay apparatus, the object of which is to prevent disturbing efi'ects from currents of neighboring lines, which, being weak, are absorbed by the condenser. The circuit, however, is also made and broken independently by the relay-armature O, which is operated by a local current of the battery 0, passing th rough the conductor 8, switch G, conductor 3, coil of the relay-instrument D", conductor 7, and circuit-breaker D. The object of this local circuit, when in operation, is to cause the armatures C to vibrate, as compelled by the circuit-breaker D, in which vibration it forms alternate contacts with the contact-points F and K, thus making and breaking the main circuit, each break connecting the induction-coil G with the ground-contact K, which may ground by connect-ion with the running-gear of the car, thus clearing the line of static effects. The rapid make and break of the circuit by this means not only enables'me to dispense with the alternate current-generators required informer inductive systems of this nature, but also produces a practically-continuous audible sound in the receiving-telephone, which, being controlled by the telegraphic sending-key, reproduces the Morse signals complete instead of incomplete, as by other systems-that is to say, the dots and dashes of the Morse alphabet are indicated in the receiving-telephone by sounds (made up of rapidly-recurring impulses) of proportional duration, while the intervals are those of complete silence. I

When the apparatus is to be thrown out of use, the switch G is opened, the armatureswitch 0 falls off its contact F, and remains open, thus breaking the circuit.

If a telephonic message is to be sent, the hand-switch E is thrown against the contactpoint 6. follows: From the helix 0, by the conductor A, armature 0, point F, conductors 4 3, thence through the telephone-receiver E, contactpoint 6, switch E, conductor 1, and condenser L, key 0, and conductor A, back to the helix 0.

The course of the current then is as If a telegraphic message is to be received, the switch E is thrown against the contactpoint e. The course of the current is then as follows: From helix 0, by conductor A, armature 0, point F, conductors 4. 5, relay E,conductor 2, point e, switch E, conductor 1, and condenser L, key 0, and conductor A, back to the helix 0.

In sending a telegraphic message the manipulationot' the key 0 alternately breaks the lastdescribed circuit, and by depression against the conducting-point 6 brings into play the local battery H, traversing a new circuit, as follows: From battery H, through conductor 6, key 0', conductor A, through the helix 0, over conductor A, through armature 0". point F, and conductors 4 and 5, to battery H.

The operation of the sounder J by means of the third local circuit operated by battery I, will be readily understood, said local current being from battery I through 9, sounder J,

conductor 10, and the armature-relay E The action of the armature G, as will readily be understood, is twofold-first, in making and breaking the local circuit of battery H when signals are being transmitted from the car, by which the battery-current is broken up into impulses, which correspondingly magnetizes the core of the suspended helix 0, which in turn acts inductively upon the conducting-helices B and B, and, second, in connecting the conductors after each break with the earth through the ground-wire K, thus clearing the conductors of the static elfects of the currents after each break. \V hen the switch G is permanently opened, the helix 0 is connected to ground, and the entire apparatus is thrown out of circuit for any purpose, such as repairs. The apparatus thus described is the same both for the moving vehicles and for the track-circuits. The latter may also be operated for transmission or reception of signals by induction, as indicated in Fig. 2, by placinga helix, 0*, in the position shown, and connectingit with apparatus similar to that described, by means of conductors A and A; or the impulses may be sent directly to the line-conductors B and B, or received directly therefrom by extending the helix-wires into the conductors A and A, as shown in Fig. 8, in which figure 0 represents the helix of the .moving vehicle.

The apparatus exhibited in Fig. 5 shows a helix, 0 similar to C, and with the terminals of the wires connected in circuit with the battery B, telegraph-key T, with the telephone T interposed in shunt, the operation being substantially as before indicated.

The conductors B and B may be laid between the rails of the track upon the ties and suitably boxed for their protection.

The construction of the helix 0 has already been suificiently indicated to those familiar with the state of the art.

I claim as my invention and desire to secure by Letters Patent of the United States- 1. In a system of electromagnetic communication to and from moving vehicles, or from said vehicles to a fixed station, a double electric-conducting path forming a continuous circuit extending in lines parallel to the path of the vehicle, in combination with an oblong helix suspended from said vehicle having its larger sides arranged parallel and in suitable inductive proximity to said electric path, each side of said moving helix being within inductive proximity to the corresponding side of the double electricconducting path, substantially as set forth.

2. In a system of ,communication of the character described, an insulated helix extending at each side of the path of the moving vehicle and forming a continuous metallic circuit, in combination with suitable apparatus at the fixed station or stations for transmitting and receiving signals by means of induct-ion to or from the vehicle moving in inductive proximity to said conducting-helix, substantially as set forth.

3. In a system of communication of the character described, an electric conductor con stituting a continuous metallic circuit arranged at both sides of and parallel with the path of the vehicle, in combination with an oblong helix secured upon the vehicle and provided with signal sending and receiving apparatus upon the same in normally-open circuit for the transmission and reception of signals upon the line-conductor, substantially as set forth.

4. In a system of electric communication of the character described, a continuous metallic conductor arranged to carry the outgoing and return currents in opposite directions along the path of the vehicle, in combination with an oblong helix carried upon the vehicle in suitable inductive relation to said line-conductor, whereby electric impulses upon said line-conductor are repeated simultaneously and inductively upon the helix carried by the vehicle, as and for the purpose set forth.

5. In a' system of electro-magnetic communication of the character described. a helix having an endless core iusubstantially rectangular or oblong form attached to'the vehicle in such manner that its parallel sides are car ried in inductive proximity to the fixed hellcal conductor extending along the vehicle path at both sides, in' combination with such fixed conductor, substantially as set forth.

6. In a system of electro-magnetic communication of the character described, the combination of a helix constituting a continuous metallic conducting-oircuitsurrounding an inductive core and extending in parallel outgoing and return paths along the path of the said vehicle, and an oblong couducting-helix carried by the vehicle, with devices, substantiall y such as described, for the inductive transmission and reception of signals.

7. The combination, ina system of electrical transmission of the character described, of a circuit-breaker in a local-battery circuit, the relay in the main circuit, the telegraphic key, the condenser, and the telephonic receiver, substantially as set forth.

In testimony whereof Ihavc hereunto set my hand in the presence of two subscribing witnesses.

GRANVILLE T. WOODS. Witnesses:

G. M. Cassa'r'r, ABRAM MAY. 

